Merge pull request #22 from bbockelm/generic_http

Add support for more generic HTTP prefixes
PelicanPlatform · Mar 26, 2024 · a0eb944 · a0eb944
2 parents a7586b7 + 57dc71e
commit a0eb944
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Showing 3 changed files with 52 additions and 26 deletions.
diff --git a/src/HTTPFile.cc b/src/HTTPFile.cc
@@ -52,31 +52,42 @@ HTTPFile::HTTPFile(XrdSysError &log, HTTPFileSystem *oss) :
     last_modified(0)
 {}
 
+// Ensures that path is of the form /storagePrefix/object and returns
+// the resulting object value.  The storagePrefix does not necessarily begin
+// with '/'
+//
+// Examples:
+// /foo/bar, /foo/bar/baz -> baz
+// storage.com/foo, /storage.com/foo/bar -> bar
+// /baz, /foo/bar -> error
 int
-parse_path( const std::string & hname, const char * path, std::string & object ) {
-    const std::filesystem::path p(path);
-    const std::filesystem::path h(hname);
+parse_path(const std::string &storagePrefixStr, const char *pathStr, std::string &object) {
+    const std::filesystem::path storagePath(pathStr);
+    const std::filesystem::path storagePrefix(storagePrefixStr);
 
-    auto prefixComponents = h.begin();
-    auto pathComponents = p.begin();
+    auto prefixComponents = storagePrefix.begin();
+    auto pathComponents = storagePath.begin();
 
     std::filesystem::path full;
     std::filesystem::path prefix;
 
-    pathComponents++; // The path will begin with '/' while the hostname will not. Skip the first slash for comparison
+    pathComponents++;
+    if (!storagePrefixStr.empty() && storagePrefixStr[0] == '/') {
+        prefixComponents++;
+    }
 
-    while (prefixComponents != h.end() && *prefixComponents == *pathComponents ) {
+    while (prefixComponents != storagePrefix.end() && *prefixComponents == *pathComponents ) {
         full /= *prefixComponents++;
         prefix /= *pathComponents++;
     }
 
     // Check that nothing diverged before reaching end of service name
-    if (prefixComponents != h.end()) {
+    if (prefixComponents != storagePrefix.end()) {
         return -ENOENT;
     }
 
     std::filesystem::path obj_path;
-    while (pathComponents != p.end()) {
+    while (pathComponents != storagePath.end()) {
         obj_path /= *pathComponents++;
     }
 
@@ -90,12 +101,17 @@ HTTPFile::Open(const char *path, int Oflag, mode_t Mode, XrdOucEnv &env)
 {
     auto configured_hostname = m_oss->getHTTPHostName();
     auto configured_hostUrl = m_oss->getHTTPHostUrl();
+    const auto &configured_url_base = m_oss->getHTTPUrlBase();
+    if (!configured_url_base.empty()) {
+        configured_hostUrl = configured_url_base;
+        configured_hostname = m_oss->getStoragePrefix();
+    }
 
     //
     // Check the path for validity.
     //
     std::string object;
-    int rv = parse_path( configured_hostname, path, object );
+    int rv = parse_path(configured_hostname, path, object);
 
     if( rv != 0 ) { return rv; }
 
@@ -136,10 +152,10 @@ HTTPFile::Read(void *buffer, off_t offset, size_t size)
 int
 HTTPFile::Fstat(struct stat *buff)
 {
-    m_log.Log(LogMask::Debug, "HTTPFile::Fstat", "About to perform HTTPFile::Fstat(): hostname / object", hostname.c_str(), object.c_str());
+    m_log.Log(LogMask::Debug, "HTTPFile::Fstat", "About to perform HTTPFile::Fstat():", hostUrl.c_str(), object.c_str());
     HTTPHead head(
-        this->hostUrl,
-        this->object,
+        hostUrl,
+        object,
         m_log
     );
 

diff --git a/src/HTTPFileSystem.cc b/src/HTTPFileSystem.cc
@@ -108,19 +108,25 @@ HTTPFileSystem::Config(XrdSysLogger *lp, const char *configfn)
         if(! temporary) { continue; }
         value = temporary;
 
-        if(! handle_required_config( attribute, "httpserver.host_name",
-            value, this->http_host_name ) ) { Config.Close(); return false; }
-        if(! handle_required_config( attribute, "httpserver.host_url",
-            value, this->http_host_url ) ) { Config.Close(); return false; }
+        if (!handle_required_config(attribute, "httpserver.host_name", value, http_host_name) ||
+            !handle_required_config(attribute, "httpserver.host_url", value, http_host_url) ||
+            !handle_required_config(attribute, "httpserver.url_base", value, m_url_base) ||
+            !handle_required_config(attribute, "httpserver.storage_prefix", value, m_storage_prefix))
+        {
+            Config.Close();
+            return false;
+        }
     }
 
-    if( this->http_host_name.empty() ) {
-        m_log.Emsg("Config", "httpserver.host_name not specified");
-        return false;
-    }
-    if( this->http_host_url.empty() ) {
-        m_log.Emsg("Config", "httpserver.host_url not specified");
-        return false;
+    if (m_url_base.empty()) {
+        if (http_host_name.empty()) {
+            m_log.Emsg("Config", "httpserver.host_name not specified; this or httpserver.url_base are required");
+            return false;
+        }
+        if (http_host_url.empty()) {
+            m_log.Emsg("Config", "httpserver.host_url not specified; this or httpserver.url_base are required");
+            return false;
+        }
     }
 
     int retc = Config.LastError();

diff --git a/src/HTTPFileSystem.hh b/src/HTTPFileSystem.hh
@@ -75,8 +75,10 @@ public:
     int       Lfn2Pfn(const char *Path, char *buff, int blen) {return -ENOSYS;}
     const char       *Lfn2Pfn(const char *Path, char *buff, int blen, int &rc) {return nullptr;}
 
-    const std::string & getHTTPHostName() const { return http_host_name; }
-    const std::string & getHTTPHostUrl() const { return http_host_url; }
+    const std::string &getHTTPHostName() const {return http_host_name;}
+    const std::string &getHTTPHostUrl() const {return http_host_url;}
+    const std::string &getHTTPUrlBase() const {return m_url_base;}
+    const std::string &getStoragePrefix() const {return m_storage_prefix;}
 
 protected:
     XrdOucEnv *m_env;
@@ -92,4 +94,6 @@ protected:
 private:
     std::string http_host_name;
     std::string http_host_url;
+    std::string m_url_base;
+    std::string m_storage_prefix;
 };